Hot-water steam flashing powergenerating apparatus and method with feed and furnace regulation



Oct. 14, 1947. J s vm JR 2,429,035

HOT WATER STEAM FLASHING POWER-GENERATING APPARATUS AND METHOD WITH FEED AND.FURNACE REGULATION Filed April 30, 1945 T '2 Sheets-Sheet 1 Inventpr dBbn 5212062 9, J

Oct. 14, 1947. STEWNG, JR 2,429,035.

HOT WATER STEAM FLASHING FOWER-GIEIHERA'IING APPARATUS AND METHOD WITH FEED AND FURNACE REGULATION Filed April 30, 1.945 2 Sheets-Sheet 2 J3 a I a) I Inventor Patented on. 14, 1941 HOT-WATER STEAM FLASHING rowan- GENERATING APPARATUS AND METHOD wrrn FEED AND FURNACE REGULATION John Steving, Jr., Berthoud, c010.

, Application April 30, 1945, Serial No. 591,184

' 4 Claims. I '(Cl. 60-106) This invention relates to a novel method of and. apparatus for generating power from steam.

The primary object of the present invention is to most economically and effectively operate a steam motor by greatly conserving heat and energy, so that a relatively small water heater, that consumes a relatively small amount of fuel, may be utilized in place of an elaborate and expensive steam-generating apparatus.

In the conventional method of operating steam motors, it is the common practice to generate steam externally oi the motor and within an elaborate and expensive steam generator whose operation requires the consumption of considerable quantities of fuel, and to then conduct the steam from the steam space of the steam generator to the steam motor for utilizing its energy in the generation of power. Considerable heat and energy is lost from the steam in its passage to the motor, and water or condensed steam is supplied to the steam generator at a relatively low temperature so that considerable heat is required to convert it into steam.

In accordance with the present invention, the water is heated to a relatively high temperature considerably above its boiling point, and is caused to remain in liquid form by maintaining it under high pressure in the heater. The highly heated water under high pressure is injected into the steam motor at timed intervals so that it expands in the motor and is instantly converted to steam directly within the motor for driving the latter. The combined, heat, pressure and expansion cause efilcient operation of the motor without loss of heat and pressure. In addition, the present invention provides for exhausting and forcing the spent steam under pressure from the motor into an exhaust receiver, maintaining the exhaust receiver at a temperature to cause the steam under pressure therein to be converted in- .to hot water, and periodically forcing the hot water back to the water heater for repressuring and reheating to the said high pressure and temhighly heated water under high pressure I the motor.

valve controlled by a governor responsive to the speed of the motor, said measuring valve controlling the amount of condensed steam or water supplied to an injection pump which injects the into The exact nature of the present invention will become apparent from the iollowing description when considered in connection with the accompanying drawings. i

In the drawings: 1

Figure 1 is a somewhat diagrammatic view, partly in elevation and partly in vertical section, showing a power-generating apparatus embodying the present invention and employing a steam motor or engine of the reciprocating piston type.

Figure 2 is an enlarged vertical section through the thermo-pressure device forming part of the apparatus shown in Figure 1.

Figure 3 is a fragmentary horizontal section taken substantially on line 3-3 of Figure 1.

Figure 4 is an enlarged section through the injection pump taken on line 4-4 of Figure 3.

Figure 5 is an enlarged plan view of the measuring valve forming part of the pump shown in Figure 4.

Referring in detail to the drawings, I have illustrated the present invention in-connection with a steam'motor of the conventional reciprocating.

type in which a piston 5 is movable in a cylinder 6 and operatively connected to crank I by a connecting rod 8, crank I being carried by a drive shaft 9 within a crank case ill. The motor also includes a cam shaft ll operated in the usual manner by gearing (not shown) from the drive shaft 9. The cam shaft ll carries cams l2 and I3, for a purpose which will presently be described.

Cylinder 6 is provided with an exhaust passage i=4 arranged to be uncovered when the piston 5 approaches the limit of its inward or power stroke, and this passage communicates with an exhaust receiver l5 having a cooling coil l6 therein. Also, cylinder 6 is provided at the top with an exhaust chamber ll which is in constant communication with the exhaust receiver l5 by way of a conduit or pipe l8. Communication between the cylinder 6 and the chamber I1 is controlled by a normally seated valve mm.- is periodically opened at predetermined intervals by an operating connection between the same and the cam l2 which includes a rocker 20 hearing at one end on the upper end of the stem of valve l9 and at its other end on a vertical push rod 2| whose lower end is arranged in the path of the cam I2. I

Arranged to receive the condensed steam or hot water from the exhaust receiver l5 by way of a pipe 22 is the cylinder 23 of an injection pump, and said pipe 22 has a check valve 22 to prevent return of the condensed steam or hot water from the cylinder of pump 23 back to the receiver l5. The pump includes a piston or plunger 24 reciprocable in cylinder 24 and normally yieldingly retracted into engagement with the cam l3 by means of a helical compression spring 25. When piston 24 is retracted, a quantity of the hot water is drawn from receiver l5 into cylinder 23 by said piston, and cam I3 periodically actuates piston 24 for discharging this quantity of hot water through an outlet; pipe 26. The quantity of hot water drawn into cylinder 23 by piston 24 is measured by means of a measuring valve 21 operatively connected at 28 with a governor 29 suitably driven from the drive shaft 9 of the motor.

' Valve 21 consists of a sleeve rotatably journaled on the cylinder 23 and within a jacket 30 surrounding and in spaced relation to the cylinder 23. The arrangement is such that the valve 2! is rotatably adjusted according to the speed of the motor so as to regulate the quantity of hot water admitted to the pump in accordance with the motor requirements. Gradual regulation of the amount of hot water admitted to the cylinder 23 is satisfactorily accomplished by providing the valve 21 with a triangular inlet port 21'.

The invention also contemplates the provision of a water heater, and this water heater has been illustrated by way of example as including a heating coil 3| whose lower portion 3| possesses a predetermined coefficient of expansion. A burner 32 for heating the water in the coil 3| is controlled by a valve 32 whose movable member 32a is operatively connected by a link 32b with one end of a lever 32c. Lever 320 is pivoted between its ends at 320. to a suitable supporting bracket 32c, and the other end of said lever is pivoted at 32) to an end of the lower portion 3| of the heating coil 3|. When the coil portion 3| is heated to a predetermined degree, it expands and closes valve member 32a. through the connections described. On the other hand, cooling of the coil portion 3| below the predetermined temperature causes its contraction and opening of the valve member 32a. In this way, a thermostatic control is provided for the burner 32 so as to maintain the temperature of the water in the coil 3| at a predetermined point. The discharge pipe 26 is connected to the upper end of coil 3|, and the other end of coil 3| is connected to a thermo-pressure device by a pipe 33, as shown in Figures 1 and 2. This thermo-pressure device includes a spring-closed and pressure-opened check valve 330 whose inlet is connected with pipe 33 and whose outlet is connected by a pipe 33?) with the receiver l5. The thermo-pressure device further includes a thermostatically controlled injection valve having its inlet connected by a pipe 330 with pipe 33 and provided with an outlet provided with an injection nozzle 33d arranged to discharge into the cylinder 6 at the upper end of the latter above the upper limit of travel of piston 5. The inlet of the injection valve is controlled by a thermostatically operated valve member 33e, while the outlet thereof is controlled by a spring-seated and pressure-opened valve 33f. Valve member 33c .is operatively connected by a lever 35 with one end of a rod 36 arranged in the casing 310i the injection valve and having a low coeflicient of expansion somewhat lower than that of the casing 31. The arrangement is such as to hold the pressure and temperature of the working fluid within the proper limits so that water will convert to steam when expanded in the working cylinder 6. When the temperature of the working fluid is too low, valve member 33c will close communication to the injection nozzle 33d, and the fluid will by-pass through the check valve 33a and return to the chamber l5. On the other hand, when the temperature of the working fluid is sufficiently high, valve 33c will open so that the working fluid will open valve 33) and pass to the injection nozzle 33d, instead of by-passing through valve 33a back to receiver l5. The seat ing spring of valve 33 is indicated at 38, and it is of lesser strength than the spring of 33a So that the pressure of the working fluid will open valve 33 and will not open valve 3311 when valve member 33s is open. A check valve 39 is arranged in the discharge pipe 26, and its function is to permit the injection pump to force the water to the coil 3| and to prevent the water from returning from said coil to the pump.

In the present system or apparatus, water is heated and kept under high pressure in the water heater. Preferably, the water is heated to about 1000 F. and kept at a pressure of about 3,000 pounds, the temperature and pressure being regulated by the thermo-pressure device. At the correct point of the stroke of piston 5, the working fluid is injected into the cylinder 6 by the injection pump, and such working fluid or liquid is instantly converted to steam as it expands and lowers in pressure within the cylinder 6. This occurs from the internal latent heat of the liquid, and the pressure drop at this stage is from 3,000 pounds to approximately 1,250 pounds. The injection of the working fluid into cylinder 6 by the pump discontinues at a predetermined point in the cycle when the piston 24 completes its pressure stroke, and the steam is allowed to expand adiabatically until near the end of the power stroke of piston 5, when it is exhausted through passage I4 into the exhaust receiver I5. As the piston moves on its return stroke, the secondary exhaust valve H! is opened, and the remaining steam in the cylinder is forced into the exhaust receiver l5 by way of pipe l8. Due to the pressure of the returning piston on the steam, the steam in the chamber I5 is maintained under pressure for converting it to water. Any slight cooling that may be additionally needed can be supplied by the coil IS.

The principal advantage of this system is higher thermal efliciency, than that afiorded by the conventional method. The generating part of the system is in no sense a flash generator or conventional boiler, the difierence being that there is no steam space. In other words, this part is completely filled with a liquid under extremely high pressure and temperature, the vaporization occurring in the cylinder during the injection of the fluid. Another advantage is that the exhaust. vapors are returned to the system and condensed mainly by pressure instead of being exhausted to the atmosphere or being entirely condensed by cooling in a condenser, as in a conventional steam plant.

The injection pump measures the required amount of water and injects it into the motor by way of the water heater. The operation of the injection pump is similar to the fuel injection system of Diesel engine, where the pump measures the required amount of fuel and jects it into the cylinder.

A practical effect of the invention is that it allows the water to expand and convert to steam directly in the motor, contrary to conventional steam practice. In such conventional practice, the water is evaporated into the steam space of a boiler, from where it is conveyed to the engine. Thermally, the latter is not as efficient as the former, because in the conventional practice, the working fluid leaves the heat-generating part of the system at its coolest point. It is particularly pointed out that the exhaust is condensed under considerable pressure and at a high temperature so that as many heat units as possible may be retained in the water and returned to the water heater. This reduces the bulk of the apparatus to a minimum.

Although the invention has been described in connection with a reciprocating engine, it is adaptable to an engine of the turbine type. Also, the invention is susceptible of various modifications and changes in details of construction illustrated and described.

What I claim is:

1. The herein described method of generating power, which method consists in heating water in a water heater to a high temperature considerably above its boiling point and causing it toremain in liquid form at such temperature by maintaining it under high pressure in the heater, automatically injecting the highly heated water under automatic control of the temperature and pressure thereof into a steam motor at timed intervals so that it expands in the motor and is instantly converted to steam therein for driving the motor, periodically exhausting and forcing the spent steam under pressure from the motor into an exhaust receiver, maintaining the exhaust .receiver at a temperature to cause the steam under pressure therein to be converted'to hot water,

and periodically forcing the hot water from the receiver back to the heater for re-pressuring and reheating said hot water to the said high pressure and temperature.

2. The herein described method of generating power, which method consists in heating water in a water heater to a high temperature considerably above its boiling point and causing it to remain in liquid form at such temperature by maintaining it under high pressure in the heater, automatically injecting the highly heated water under automatic control of the temperature and pressure thereof into a steam motor at timed intervals so that it expands in the motor and is instantly converted to steam therein for drivingthe motor,

back to the water heater according to the speed of the-motor.

3. A power-generatingapparatus of the character described comprising a water heater for heating water to a temperature considerably above its boiling point, a steam motor, means to conduct hot water from the water heater to the motor for driving the latter upon expansion of the water for conversion of the same to steam matically inject the water at timed intervals into the motor, an exhaust receiver, exhaust means whereby the'motor may periodically force the spent steam therefrom under' pressure to said exhaust receiver, and a pump operated bythe motor to periodically withdraw hot water from the exhaust receiver and force it under pressure to thehot water heater.

4. A power-generating apparatus of the character described comprising a water heater for heating water to a temperature above its boiling point, a steam motor, means to conduct hot water from the water heater to the motor for driv- 'conversionof the same to steam in the motor,

,a thermo-pressure injection device interposed pump operated by the motor to periodically withdrawhot water from the exhaust receiver and periodically exhausting and forcing the spent the quantities of hot water periodically forced force it under pressure to the hot water heater, and means to automatically measure the amount of hot water drawn from the exhaust receiver and forced to the water heater in accordance with the speed of. the motor. 7

' JOHN STEVING, JR.

REFERENCES crrEn The following references are of record in th file of this patent:

UNITED STATES PATENTS I Number Name Datev 653,436 Buck July 10, 1900 782,624 Rey Feb. 14, 1905 1,008,797 Drummond Nov. 14, 1911 1,067,101 Doble July 8, 1913 1,687,615 Hubbard Oct. 16, 1928 I FOREIGN PATENTS Number Country Date 1,842. Great Britain July 2. 1857 234,093 Great Britain Aug. 9, 1926 Great Britain Oct. 27, 1927 

